-When the aircraft is not in CRUISE yet
F-PLN Page at Origin (on Ground)
Figure 012
Vertical Revision Page
Figure 013
b
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c
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* If a constraint | prior to T/C (if it exists) is set at a | or waypoint | belonging to a SID
| or | prior to a climb alt or | speed constraint waypoint,
the constraint is a climb constraint.
* If it is set at | beyond T/D (if it exists)
a waypoint | or | belonging to a STAR | or | beyond a descent alt or | speed constraint waypoint,
the constraint is a descent one.
-When the aircraft is in CRZ, DES or APPR phase, if a constraint is set at any active primary waypoint, then it is a descent one.
-In other cases, the pilot has to choose the type upon entry of the constraint.
Speed constraint:
The speed constraint is an AT or BELOW constraint, defined
at a specified waypoint.
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If it is related to takeoff or climb (climb type constraint), it applies from the origin up to the waypoint where it is defined.
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If it is related to missed approach, it applies from the destination up to the waypoint where it is defined.
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If it is related to DES or APP (descent type constraint) it applies from the constraint waypoint down to the destination.
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If it is related to manual holding pattern, it is used for the holding target speed computation.
-The speed constraint is predicted missed if the difference between predicted speed at constrained waypoint and speed constraint value is greater than 10 kts and as long as this difference remains greater than 5 kts.
Time constraint (RTA):
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It is an aircraft time requirement to be met over a specified waypoint in lateral flight plan.
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It can be an AT, AT or BEFORE, AT or AFTER time constraint.
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-It is predicted missed if the difference between the predicted time at constrained waypoint and time constraint value is greater than 30 seconds and as long as this difference is greater than 15 seconds.
-There can be only one time constraint in the flight plan, if the pilot enters a new constraint, the previous one is automatically deleted. The time constraint may also be automatically deleted upon activation of the ENGINE OUT mode or, at transition from Approach to GO AROUND or if Alternate is enable or if the active leg is a manual holding pattern.
-At origin airport, during preflight, the pilot may also enter an estimated takeoff time (ETT) defined as a time value used as time initialization for predictions. Entry of ETT is independent of entry of time constraint (that means we may have ETT and time constraint).
d Constant Mach Segment (CMS)
_ The crew may define a CRZ segment which will be flown with a constant, crew-defined Mach. As this segment (named CMS) will be taken into account both by Predictions and Guidance, this function will allow the crew to define a comprehensive flight plan with correct fuel and time predictions.
Speed limit
The speed limit has a speed and altitude associated with it.
The speed must be a CAS. The altitude may be in altitude (ft.)
or flight level following the same logic as for altitude
constraints.
(Ref. Fig. 013)
Below the specified altitude, the aircraft is not allowed to
exceed the specified speed (except in cruise phase).
This limit does not apply to a specific lateral path but
rather to a specific altitude. There is a system default speed
limit which is 250/10000, but it is possible not to use it by
selection in the AMI file via Speed Limit Requested
Information .
There may be only two speed limits : one in CLB and one in
DES.
Cruise altitude
This is the altitude of the aircraft at the top of climb.
The cruise altitude is defined during active flight plan
initialization.
It is displayed and modifiable on INIT A page or Progress Page
(Ref. Fig. 014)
INIT A Page
Figure 014
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or
(Ref. Fig. 015)
If two cruise altitudes are defined, the first one is used as
the CRZ altitude and the second one as the step altitude (the
step is then automatically inserted in the flight plan).
Step climb-step descent
A step climb (step descent) in the flight plan occurs when the
vertical profile changes from one cruise altitude to a higher
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